Continue to refactor zoning to be more stream-based

src/Geometry.hs

@@ -29,6 +29,7 @@ import Geometry.LHS
 import ListHelp
 --import Geometry.ConvexPoly
 
+import qualified Data.Set as S
 --import Data.Maybe
 --import Data.List
 -- | Return a point a distance away from a first point towards a second point.
@@ -122,6 +123,10 @@ angleBetween v1 v2 = argV v1 - argV v2
 doublePair :: (a,a) -> [(a,a)]
 doublePair (x,y) = [(x,y),(y,x)]
 
+-- this shouldn't be here
+doublePairSet :: Ord a => (a,a) -> S.Set (a,a)
+doublePairSet (x,y) = S.fromList [(x,y),(y,x)]
+
 doubleV2 :: V2 a -> [V2 a]
 doubleV2 (V2 x y) = [V2 x y,V2 y x]
 -- split a list into triples, forms triangles from a polygon